Dual spindle router for stereotype plates



Oct. 5, 1965 H, sATRE ETAL 3,209,653

DUAL SPINDLE ROUTER FOR STEREOTYPE PLATES Oct. 5, 1965 H. sATRE ETAL 3,209,653

DUAL SPINDLE ROUTER FOR STEREOTYPE PLATES Filed June '7, 1963 6 Sheets-Sheet 2 Oct. 5, 1965 L.. H. sA'rRE ETAL 3,209,653

DUAL SPINDLE ROUTER FOR STEREOTYPE PLATES Filed June '7, 1963 6 Sheets-Sheet 3 Oct. 5, 1965 L. H. sATRE ETAL. 3,209,653

DUAL SPINDLE ROUTER FOR STEREOTYPE PLATES Filed June 7, 1963 6 Sheets-Shea?I 4 Oct. 5, 1965 L. H-SATRE ETAL 3,209,653

DUAL SPINDLE ROUTER FOR STEREOTYPE PLATES Filed June 7, 1963 6 Sheets-Sheet 5 //0 ///A7 U74 /M 576 Wwf :a

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Oct. 5, 1965 H. sATRE ETAL 3,209,653

DUAL SPINDLE ROUTER FOR STEREOTYPE PLATES Filed June 7, 1965 @ff/Z 6 Sheets-Sheet 6 QM ilgl TT United States Patent O 3,209,653 DUAL SPINDLE ROUTER FR STEREOTYPE PLATES Leland H. Satre and Charles L. Burdett, Whittier, and Jasper A. Burdett, Norwalk, Calif., assignors, by mesne assignments, to Leland H. Satre, North Plainfield, NJ.

Filed June 7, 1963, Ser. No. 286,271 18 Claims. (Cl. 90-15) This invention relates to routing machines and, more particularly, to apparatus for routing semi-cylindrically curved plates such as stereotype plates for newspaper letterpresses.

Presently known machines for stereotype plate routing provide only a single rotary spindle in which a routing tool is held. The spindle usually is reciprocable toward and away from a stereotype plate which is mounted on a rotatable support for manually powered movement about an axis perpendicular to the path of reciprocation of the spindle. The spindle is equipped for manual or power driven movement parallel to the axis of rotation of the stereotype plate.

Since existing routing machines are equipped with only a single tool-holding spindle for each plate, it is necessary to shut down the machine when a change in size of the routing tool is required. For example, in routing out non-printing portions of a stereotype plate used for printing one color of a multi-color comic section, a large diameter routing tool is used for roughing out the nonprinting portions of the plate. A small diameter routing tool is used to finish the routing process.

Letterpresses are so constructed that two identical plates are used in each printing run. Each plate is semi-cylindrical. The plates are mounted back-to-back on a letterpress printing roll so that two sheets of printed matter, say, a newspaper page, are printed with each rotation of the printing roll. Because existing routing machines provide only a single tool-holding spindle for each plate, it is necessary to rough out each plate and then to insert a smaller diameter routing tool into the machine to finish the routing operation. Alternatively, two separate routing machines must be used. This latter practice requires that the heavy stereotype plates be moved between machines.

The present invention provides a traversing head carrying a pair of reciprocal spindles so that two different sizes of routing tools may be carried by the pair of spindles for each plate. This provides that it is not necessary to completely shut down the machine to change from roughing to finishing tools. A preferred embodiment of the present invention provides a pair of traversable heads, each carrying a pair of reciprocal spindles. The heads are linked together for movement as a pair so that both of a pair of identical stereotype plates may be routed simultaneously. i

Generally speaking, the present invention resides in a routing machine. The machine includes means for mounting a semi-cylindrically curved plate concentric to a horizontal axis. A router head is provided together with means for mounting the router head for movement along a path above and parallel to the horizontal axis. Also, means are provided for moving the router head along the path. In such a routing machine the improvement provided by the present invention includes a pair of substantially vertically disposed spindles, each adapted for releasably receiving a routing tool at its lower end. Mounting means are provided for mounting each spindle to the router head for rotation about a substantially vertical axis and for reciprocation along the Iaxis between a raised and a lowered position of the spindle. Controllable means are provided for moving a selected one of n 3,2n9,653 Patented Oct.. 5, 1965 JCC the pair of spindles to its lowered position and for rotating the selected spindle. The invention further includes interlock means for controlling the controllable means for rotating the lowered spindle in a direction for cutting operation of the routing tool and for assuring that the other spindle is raised when the selected spindle is lowered.

In a routing apparatus of the type described above, the present invention also provides improved cutting shield means for shielding the spindle from cuttings produced by operative engagement of a router tool with the curved plate. The routing apparatus includes stationary cuttings shield means disposed Iinteriorly of an enclosure for the plate mounting means and the router head. The stationary cuttings shield means is disposed between the plate mounting means and the router heady and denes an opening therethrough through which the spindles depend as the router head is moved along its path. Movable cuttings shield means are provided for closing the opening in the stationary shield means. The movable shield means are movably connected to the stationary shield means on opposite sides of the opening and are connected to the router head for movement with the router head. The spindles pass through the movable shield means.

The above-mentioned and other features of the present invention are more fully set forth in the following detailed description of the present invention taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a routing machine according to .the present invention;

FIG. 2 is an enlarged cross-sectional elevati-on view of a portion of the mach-ine illustrated in FIG. 1 and shows the orientation of a router head relative to a curved stereotype plate;

FIG. 3 is an elevation view of a router head mounted on its supporting rails;

FIG. 4 is an enlarged top plan View of the apparatus illustrated in FIG. 3;

FIG. 5 is a fragmentary top plan view lof the spindle drive mechanism; and

FIGS. 6A and 6B together comprise a schematic diagram of the control circuitry of the routing machines shown in FIG. 1; FIG. 6 is a key showing how FIGS. 6A and 6B are related. v

In the drawings, like numerals refer to like elements of structure.

Referring initially to FIG. l, a routing machine 10 according to the present invention is illustrated. Machine 10 comprises a housing 11 defining an elongated, substantially horizontally disposed internal cavity 12 closed by a slidable door 13 and a slidable window assembly 14 which are movable together from their open position shown in FIG. l to enclose cavity 12. `A horizontal rotatable shaft 15 is disposed lengthwise of cavity 12 and is supported for rotation by suitable means (not shown). The opposite ends of shaft 15 pass through vertical shield walls 16 disposed at opposite ends of the cavity to prevent cuttings, produced by routing of stereotype plates mounted in the cavity, from escaping from the cavity. The cavity is also bounded by a lengthwise cuttings shield 17 disposed at the back of cavity 12. Two pairs of cylindrical drums 18 and 19, respectively, are secured to shaft 15 for rotation with the shaft. Each pair of drums is referred to herein as a cylinder and is adapted for receiving two semi-cylindrically configured stereotype plates, such as plate 20. The semi-cylindrical stereotype plates are of the type used in letterpresses, as, for example, in the printing of newspapers.

"One one stereotype plate 20 is illustrated in FIG. 1 so that the illustration of the present invention may be simpliiied. In practice, however, -twostereotype plates are secured to each cylinder during a routing operation. Only two of these four plates may be actually operated upon at the same time during the routing process. The other of the two plates may be dummy plates mounted to the cylinder to provide dynamic balance to the shaft 15, or Vfou-r plates may be loaded on the cylinders and after the first set is routed, the second set may then be routed. Some printing establishments have two printing presses which receive stereotype plates of different diameter. In this case, it is desirable to have a routing machine in which each cylinder has a different radius over 180 of its circumference than the remaining 180 so that plates for both presses may be routed on the same machine.

A pair of router heads 22, 23 are mounted in housing 11 upon a pair of guide rails 24 (see FIG. 2) for movement along a straight path disposed above and parallel to the axis of rotation of shaft 15. Two rotatable spindle assemblies 25 and 26, respectively, are mounted in each router head for rotation about substantially parallel vertical axes. Actually, the axes of each pair of spindles are slightly skew to one another so that the axis of each Aspindle is normal to axis of shaft 15 and intersects the axis of the shaft.

.and 23 along the path parallel to shaft 15. The machine also includes a control handle 29 for controlling rotation of shaft 15. A control handle 27 is provided for shifting from manual to power driven operation of shaft 15. A

.control handle 30 is provided for adjusting the position of shaft 15 toward or away from the horizontal path of movement of router heads 22 and 23.- A control panel 'is provided on housing 11 and includes a spindle selector switch 31, Aand a switch 32 for selecting the spindle equipped with the tool the operator desires to use; switch 32 also functions as a start button when depressed. A stop button 33 is also provided together with a plurality of indicator lights 34-36. A foot peddle 37 is provided for moving the selected spindle o-r spindles toward and away from shaft 15 as the operator requires. A master power control switch 38 is also provided.

In order that an 'operator of the routing machine may clearly see the workpiece being routed, a pair of fluorescent lamp tubes 39 are provided in cavity 12 and are disposed lengthwise of the cavity on the opposite sides of spindles and 26'. v

Router heads 22 and 23 are essentially identical and therefore only head 23 is illustrated in detail in the accompanying drawings and is described herein in detail. As lillustrated most clearly in FIGS. 2, 3, and 4, router head 23 preferably is a rectangular block having a forward end 40, a preferably vertically disposed rear surface 41, an upper surface 42, a lower surface 43, and left and right side surfaces 44 and 45, respectively. A pair of horizontally disposed parallel bores 46 are provided through head 23 adjacent the forward and rear ends of the head. Bores 46 are lined by journal sleeves 47 which circumferentially engage respective ones of guide rails 24 so that the head is slidably movable lengthwise of the guide rails. As illustrated in FIG. 2, it is preferred that guide rails 24 are hollow along their elongate extent between shield walls 16 which support the rails in cooperating apertures of the shield walls so that the interiors of the rail tubes open into the housing at opposite ends of the cavity.

A boss portion 48 is raised from router head upper surface 42. A smiliar boss portion 49 extends from bottom surface 43 of the router head and is aligned with boss portion 48.

A pair of parallel bores 50 are formed through router head 23 so as to pass through boss portions 48 and 49. As shown most clearly in FIGS. 3 and 4, bores 50 define substantially vertically disposed receptacles for spindles 25 and 26. The bores are offset a preselected amount relative to one another transversely of the path of movement of the router head along rails 24. The upper extent 51 of each bore 50 is of greater diameter than the lower extent of the bore so as to define an upwardly opening annular shoulder 52 in the bore. The upper end of the portion of each spindle which is engaged within a bore is of a diameter which makes a sliding fit within enlarged portion 51 of the bore. A compression spring 53 is disposed in the enlarged diameter portion 51 of each bore and is supported at its lower end by shoulder S2; at its upper end the spring engages a downwardly opening shoulder defined by the spindle assembly. The spindles are reciprocable in bores 50 between raised and lowered positions of the spindles. Springs 53 bias the spindles into their raised positions, as shown in FIG. 2.

The upper end of each spindle assembly defines a pulley element 54 which is engageable with a drive belt for rotation of the spindle in a manner described below.

The present invention includes apparatus for moving one or the other of the spindles in each router head into its lowered position for cutting engagement of a router tool 55 with the upper surface of stereotype plate 20. Each spindle has its own reciprocating mechanism, but these mechanisms in each router head are interlocked so that, of the pair of spindles in each router head, only the spindle selected by the operator by operation of switch 32, one or the other, but not both, of the spindles is movable into its lowered cutting position when the foot pedal is depressed or when a switch (see FIG. 6B) is operated to override foot pedal 37. A vertically elongated slot 56 is formed from the upper extent of each bore through the router head to the adjacent side of the router head. A pin 57 is extended from the upper end of each spindle through the cooperating slot 56 to an end spaced outwardly beyond the respective side surface of the router head. Each pin is engaged in a cooperating aperture 58 formed in a lever 59 which has its forward or fulcrum end pivotally connected, as by a fulcrum pin 60, to a raised lug 61 defined by the router head adjacent the forward end of the router head. The rear end of each lever 59 is connected, as by a link 62, to a corresponding armature 63 of a group of solenoids 64A, 64B, 64C, and 64D. Solenoids 64A and 64B are coupled to the left and right spindles, respectively, of left router head 22 and solenoids 64C and 64D are coupled to the left and right spindles, respectively, of right router head 23. Each pair of solenoids is supported on a horizontally extending flange 65 of a support member 66 secured to rear surface 41 of router head 23. Among levers 59, the distance between pin 57 and pin 60 is equal. Since the spindles are offset transversely of the path along which router head 23 moves, lugs 61 are offset a like amount from forward end 40 of the head. When a solenoid is actuated, its armature is drawn downwardly to pivot lever 59 about its fulcrum 60 and thereby draw pin 57 downwardly. As a result, actuation of a solenoid provides that the spindle with which the solenoid is associated is moved downwardly from its raised to its lowered position against the bias of spring 53. De-energization of the solenoid allows upward movement of the spindle as spring 53 becomes effective. The elongate extent of slot 56 determines the amount of reciprocation of the spindle in its bore 50.

As illustrated in FIG. 5, the drive mechanism for rotating spindles 25 and 26 includes, in housing 11, a drive pulley 67 driven by a motor 68. Pulley 67 preferably is'y disposed in a horizontal plane and is located in the upper` extent of the housing at one end thereof. At the other end of the housing, and preferably in the same plane as: pulley 67, a belt tensioning pulley 69 is mounted on a rotatable shaft 70. A spindle drive belt 71 is engaged over these pulleys and is also engageable with the drive pulleys 54 of the spindles 25 and 26. As illustrated most clearly in FIG. 5, router heads 22 and 23 are supported on rails 24 forwardly of pulleys 67 and 69 so thatspindle pulleys 54 are substantially in the same plane as the belt drive and tightening pulleys. As mentioned above, spindles 25 and 26 are offset transversely of the path of movement of the router heads along rails 24. Spindles 25 are disposed forwardly and to the left of spindles 26. Progressing to the right from belt tensioning pulley 69, belt 71 is irst engaged around left spindle 25 of router head 23 and then around spindle 26 of the same router head. The belt then passes around the left spindle of router head 22 and then around the other spindle of the left router head prior to passing around drive pulley 67. The portion of belt 71 between belt tensioning pulley 69 and spindle 25 of router head 23 is parallel to the portion of the belt between spindle 26 of router head 22 and drive pulley 67 so that there is no tendency for shaft 70 to be moved as the router heads are moved along rails 24.

The belt drive system provided by the present invention allows for movement of the route-r heads along the rails While the selected spindle is rotatively driven. The belt drive system shown has no idlers and therefore is simplied over previously known routing machines with the result that there are fewer parts to wear and require replacement than if idlers were provided.

The router heads are so disposed relative to the plane in which belt 71 moves that the lower extent of a spindle pulley is aligned with the lower edge of the belt when the spindle is in its raised position, and the upper extent of the spindle pulley is aligned with the upper edge of the belt when the spindle is lowered (see FIG. 3).

Conventional routing tools are so manufactured that they must be rotated in a clockwise direction in order to be effective to rout a workpiece with which they are engaged. An examination of FIG. 5, however, will indicate that if spindle 25 rotates in a clockwise direction, spindle 26 will rotate in a counterclockwise direction. Both sets of spindles cannot be rotated in a clockwise direction at the same time. Accordingly, the present invention includes interlock means for controlling motor 67 for rotating a lowered spindle in a direction such that the routing tool engaged in the lowered spindle is rotated for effective routing operation. In the present invention, such interlock means are coupled to solenoids 64 and to the means which are operated to select which of the spindles is to be used at any given time in a routing operation. When the foot pedal is actuated to lower a spindle, the solenoid 64 with which it is associated is energized. Motor 68 is controlled accordingly so that belt 71 moves in a direction whereby the lowered spindle is rotated clockwise about its axis of rotation. For example, with reference to router head 23, if spindle 26 has been selected by the operator to be lowered, motor 68 will be controlled to rotate drive pulley 67 in a counterclockwise direction. Spindle 26 will be lowered when foot pedal 37 is depressed since solenoid 64D will then be energized. If at any time spindle 25 is selected, the direction of rotation of motor 68 is reversed such that pulley 67 rotates clockwise to rotate spindle 25 in a clockwise direction, and solenoid 64C will be energized when foot pedal 37 is depressed.

Shaft 70, to which pulley 69 Vis mounted, is resiliently biased laterally of its axis of rotation in order that the tension in belt 71 is maintained at a predetermined level.

A routing machine according to the present invention includes means for providing traversing movement of router heads 22 and 23 reciprocally along a straight path dened by rails 24. In such reciprocal movement, router heads 22 and 23 are maintained a predetermined distance apart from one another, a distance equal to the spacing between corresponding points of stereotype plates secured to drum pairs 18 and 19 on shaft 15. Accordingly, when identical stereotype plates are mounted to shaft in axially aligned relation, both plates may be routed simultaneously by tandem movement of the router heads.

The mechanism for moving router heads 22 and 23 along guide rails 24 includes a tie bar 73 rigidly linking the router heads so as to space them a predetermined distance apart from one another. Tie bar 73 is engaged between aligned upstanding lugs 74 disposed on the upper surfaces of the respective router heads. As shown most clearly in FIG. 4, each router head defines a second upstanding lug 75 on the side of the router head opposite from lug 74. Corresponding ends of a chain 76 are secured to lugs 75. Preferably, lugs 75 are aligned with one another and with lugs 74.

FIG. 3 shows chain 76 extending through an aperture 77 in end panel 16 of housing 11 to engage a rotatable sprocket 78 secured to a shaft 79 which is rotatable either manually or automatically by means described below. From sprocket 78, chain 76 passes interiorly of rear guide rail 24 to the opposite end of the guide rail where it is engaged with a similar sprocket (not shown). The chain is then passed through the adjacent end panel of the housing to engage lug 75 of router head 22. Sprocket 78 is selectively operable for rotation either in a clockwise or counterclockwise direction for movement of the pair of router heads to the right or to the left, respectively. Manually powered rotation of shaft 79 is controlled by hand wheel 28 mounted exteriorly of the front of housing 11.

Shield means for protecting the relatively movable parts of the router head from damage by cuttings or chips produced by routing a stereotype plate are provided by the present invention. As noted above, a stationary cuttings shield member 17 is provided longitudinally of .housing cavity 12 adjacent the rear of the housing. Preferably, as shown in FIG. 2, stationary shielding member 17 extends upwardly and forwardly from the rear portion `of the housing to a supporting member 80 which extends longitudinally of the cavity. Support member 80 is disposed parallel to the path along which router heads 22 and 23 move. A second support member 81 is disposed parallel to rst support member 80 on the opposite sides of spindles 25 and 26 and supports the rearward extent of a second stationary shielding member 82 which preferably extends into sealing engagement with window 14 in a manner which is conventional and is therefore not shown. Preferably, support members 80 and 81 are provided in the form of angle bars which have one leg thereof disposed vertically parallel to the vertical axes of rotation of the spindles and parallel to the path of movement of the routing heads along rails 24. The vertically disposed flanges of the angle bars are disposed between the spindles and fluorescent lighting tubes 39 and deline an elongated opening lengthwise of cavity 12 through which spindles 25 and 26 depend toward stereotype plate 20. As illustrated most clearly in FIG. 2, it is preferred that the upper surfaces of supports 80 and 81 be recessed, as at 83, to provide parallel guideways for a movable cuttings shield member 85, which spans the opening between support members 80 and 81 along the entire extent of cavity 12. A retainer member 84, preferably provided in the form of an elongated hat bar or strip, is secured to the upper extents of each support member in cooperation with recess 83 to retain movable cuttings shield member 85 in the recesses.

Movable shielding member 85 preferably is provided as an elongated strip of sheet metal having resilient characteristics such that it tends to coil upon itself, much like a main spring for a watch. The metal strip is secured to the underside of each routing head by a retainer plate 86 engaged with the lower side of the strip and secured to the lower bosses 49 of the respective routing heads by a plurality of screws or the like (not shown) passing through the sheet metal strip. It is preferred that a layer of felt 87 or the like be disposed between retainer plate 86 and the underside of metal strip 85 to provide a wiper relative to spindles 25 and 26 which project through corresponding apertures in the retainer plate and the sheet metal strip.

As illustrated in FIG. 3, the movable shield strip 85 passes through a horizontal slot 88 in each panel of cavity 12 to be slidably engaged between a pair of horizontal guide members 89. Beyond these guide members, the sheet metal strip extends to a coil 90 which is maintained by the resilient characteristic of the strip. Horizontal guide members 89 are provided to uncoil the strip and to smooth the strip for engagement with recesses 83 as the router heads are moved along rails 24. It is preferred that a wiper element 91 be provided interiorly of cavity 12 adjacent the underside of strip 86 to prevent cuttings, chips, and shavings from passing through slot 88. Wiper member 91 also provides that cuttings do not interfere with smooth sliding movement of the movable shielding member in its guideway recesses 84.

From the foregoing description it will be seen that as router heads 22 and 23 are moved along their supporting rails, the movable shielding member is moved with the router heads. If the router heads are moved to the left, then the spiral coil 90 at the right end of strip 85 will be decreased while a similar coil at the left end of the strip will be increased. It is thus seen that the present invention provides an extremely compact shielding mechanism for protecting the router heads from damage by particles of metal.

FIGS. 6A and 6B together comprise a schematic diagram of the control circuitry for routing machine 10. The relationship between FIGS. 6A and 6B is shown by FIG. 6. Hand wheel 28, and hand wheels 27 and 29, control traversing of router heads 22 and 23 and rotation of shaft 15, respectively; hand wheels 27 and 29 are connected in tandem for manual rotation of shaft 15. Both hand wheels are movable toward and away from housing 11. When one of these wheels is moved away from housing 11, the mechanical mechanism controlled thereby is automatically disengaged and the corresponding powered mechanism is placed in condition for operation. The control circuitry of the machine is such that the operations of power router head traversing and power cylinder rotation cannot exist simultaneously. That is, when the router heads traverse under power, shaft rotation is manual; and when shaft is rotated under power, traversing of the heads must be manually controlled. Shaft 79 is releasably and reversibly coupled to a motor 92 by a twoeld electromagnetic clutch and to hand wheel 28 by a mechanical clutch (not shown) operated by hand wheel 28. Similarly, shaft 15 is releasably and reversibly coupled to motor 92 by the same two-field magnetic clutch (not shown). A mechanical clutch (not shown) is operated by axial movement of hand wheel 27. The clutch eld which is energized when the routing heads are traversing right, or when shaft 15 is rotating forwardly, is shown in FIG. 6B as the coil 93. The clutch field controlling router head movement to the left and shaft rotation in a backward direction is shown as the coil 94.

In describing FIGS. 6A and 6B, when reference is made to a relay, the solenoid of the relay is denoted by a numeral having no letter sufx; the contacts controlled by the solenoid have the same numeral with a letter suflix. A similar procedure is followed in describing the various switches shown in FIGS. 6A and 6B.

Contacts 28C are closed when the router heads are traversing to the right and contacts 28D are closed when the router heads traverse to the left. Similarly, contacts 27C are closed when rotation of shaft 15 is forward and contacts 27D are closed when shaft rotation is backward.

Hand wheel 28 is equipped with a dead man control when it is pulled away from housing 11 to place the router head traversing mechanism in condition for power operation. The hand wheel must be held to the right by the operator to obtain powered movement of the router heads to the right; such operation of hand wheel 28 closes contacts 28C. Similarly, the hand wheel must be held to the left to obtain powered movement of the router heads to the left; such operation of the hand wheel closes contacts 28D. Hand wheels 27 and 29 are coupled in tandem for rotation. Hand wheel 27 is equipped with a dead man control when it is pulled away from housing 11 to place the cylinder rotation mechanism in condition for power operation. Wheel 27 or 29 must be held to the right to obtain forward rotation of shaft 15; this closes contacts 27C. Similarly, hand wheel 27 or 29 must bc held to the left to obtain backward rotation of shaft 15; this closes contacts 27D. Movement of 'hand wheel 27 into its forward axial position closes a swich 27A and opens a switch 27B. Similarly, placing hand wheel 28 into its forward axial position closes a switch 28A and opens a switch 28B. These switches are so related to one another that no current can llow through motor 92 when hand wheels 27 and 28 are both disposed away from housing 11 or when both of these wheels are disposed against the housing. Current can ow through the windings of motor 92 only when one or the other of wheels 27 and 28 is in its forward axial position.

As illustrated in FIG. 6A, selector switch 31 operates two separate switch mechanisms 31A and 31B. Switch 31A is connected to solenoids 64A and 64B. Switch 31B is connected to solenoids 64C and 64D. Operation of one or the other of switches 31A and 31B selects either left router head 22 or right router head 23, respectively, for operation. Switches 31A and 31B may be closed together in order to select both router heads for operation, as when two stereotype plates are to be routed simultaneously. Assuming that switch 31A is closed, energization of solenoids 64A and 64B is controlled according to whether motor 68 is rotating clockwise or counterclockwise, respectively. The nature of rotation of motor 68 is determined by the condition of switch 32 which is provided for selecting either left or right spindle operation and for starting rotation of motor 68. Accordingly, it is preferred that switch 32 be a push button switch having two angular positions of the push button. Switch 38 is essentially an ON-OFF switch controlling connection of belt drive motor 68 to input conductors L1, L2, and L3. The field connections T1, T2, and T3 of motor` 68 are controlled by two sets of relay contacts A and 96A. The coils of relays 95 and 96 are in series with switch contacts 32A and 32B, and 32C and 32D, respectively. Current for operating the various relays in routing machine 10 is derived either from input conductor L1 or belt drive motor terminal T1. The return of such current is common to conductor L2 through return conductor R.

If it is assumed that spindle 26 of router head 23 is to be used in routing a stereotype plate, selector switch 31 is set so that contacts 31B are closed. If it is desired that this spindle be held down continuously, then switch is also closed. On the other hand, if the machine is used for tracing a pattern on a stereotype plate, in which case the selected spindle is raised and lowered frequently, then operation of foot pedal 37 is preferred. Power control switch 38 is closed. Switch 32 is set to a position indicating that only right router head 23 is to be used and switch 32 is then operated to close contacts 32C and 32D. The circuit through solenoid 64D is then complete once either switch 37 or switch 120 is closed. Momentary closing of contact 32C energizes posed in panallel with switch contacts 32C, and to close contact 96E in series with solenoid 64D. Accordingly, solenoid 64D is energized and spindle 26 of right router head 23 is moved into its lowered position. Energization of solenoid 96 closes relay contacts 96A so that motor 68 is operated to rotate pulley 67 in a counterclockwise direction for clockwise rotation of the lowered spindle. If at any time during a routing operation, it is desired to use the other spindle of lrouter head 23, switch 32 is set accordingly and the switch is actuated to close contacts 32A and 32B. This energizes relay 95 and inactivates relay 96 so that spindle 25 is lowered and motor 68 is reversed so that the newly lowered spindle is rotated in the proper direction.

Rapid stopping of motor 68 is accomplished by a plugging operation controlled by a time delay mechanism controlling normally closed contacts 97A which connect a pair of control relays 98 and 99 to input conductor L1. Which one of relays 98 and 99 is energized at any given moment is controlled by which of relays 95 and 96 is energized. That is, energization of relay 95 energizes relay 98 and energization of relay 96 controls operation of relay 99. Assume that one of the left spindles is operating and it is suddenly desired to stop rotation of this spindle. Stop button 33 is operated. Motor control relay 95 is tie-energized but control relay 98 is maintained active through contacts 98D. Accordingly, contacts 98C across contacts 32C are closed and motor control relay 96 is energized as contacts 95C are closed with de-energization of motor control relay 95. Motor 68 therefore revers-es and according to conventional plugging te-chniques relay 96 is energized until time delay mechanism 97 times out to open contacts 97A and thereby de-energize control relay 98, motor control relay 96, and the time delay mechanism. The period required for time delay mechanism 97 to time out is adjustable in a preferred embodiment of the present invention.

A pair of overload switch contacts 100 and 101, and a window interlock switch 102 are provided in series with stop switch 33. Also provided are normally closed contacts 103A, 104A, and 105A which are maintained closed so long as the chip level, air pressure, and oil level in the machine are at proper values. Compressed air is provided for maintaining proper lubrication of the moving parts of the machine.

The present invention includes means for determining when the level of chips, produced by routing of a stereotype plate, reaches a predetermined level in cavity 12. Several pairs of probe contacts 106 are provided in the cavity. When chips accummulate to a predetermined level, they bridge the space between at least one of the pairs of probe contacts and provide a circuit through the coil of a chip control relay 103, thereby opening normally closed contacts 103A and closing contacts 103B to light indicator lamp 36. Similarly, normally closed contacts 104A and 105A are controlled by relay 104 which is energized when the oil and air pressures in the machine fall below predetermined limits.

It is preferred that the chip sensing probes 106 be operated on a low voltage (preferably 12 volts) to prevent hazard to operating personnel in case of accidental contact, and therefore a transformer 107 is provided for powering relay 103.

It was noted above that the present elevation provides for power traversing of router heads 22 and 23 parallel to the axis of shaft 15. Routing machine also provides for powered rotational movement of shaft through an arc of approximately 180. To place the mechanism for power router head traversing in operation, control handle 28 is pulled away from the front of housing 11 to close contacts 28A so that current is supplied to motor 92. This action also disengages the hand wheel from shaft 79 and engages the power drive system through positive clutches (not shown). The handle is then given a slight turn, a turn to the right for example, to close switch contacts 28C so that the automatic traversing mechanism is initially energized. Wheel 28 must be held in this position to maintain right traversing of the router heads. An initial turn to the right energizes a control relay 110. Accordingly, as control relay 110 is energized, contacts 110C, in series connection with electromagnetic clutch coil 93, are closed. The router heads then move from left to right along rails 24 as shaft 79 is rotated under power from motor 92.

A plurality of limit switches are provided in machine 10 for sensing the eXtreme limits of router head movement and the limits of rotation of shaft 115. A limit switch 112, having normally closed contacts 112A in series connection with relay 110, is provided for sensing the right limit of travel of the router heads. Similarly,

10 a limit switch 113, having normally closed contacts 113A in series connection with a second control relay 111, is provided for sensing the left limit of travel of the router heads.

Assuming that the router heads are moved under power from motor 92 from left to right but have not yet reached their right limit of travel, control relay is energized so long as contacts 28C are closed and normally closed relay contacts 111A, in series connection with relay 110, and normally closed limit switch contacts 112A are closed to maintain relay 110 energized. So long as relay 110 is energized, the clutch field controlling right movement of the router heads is energized and such movement of the router heads continues. Because cylinder rotation is under manual control, the operation of the limit switches associated with rotation of shaft 15 is not of concern. It is noted at this point, however, that a limit switch 114, having normally closed contacts 114A in series connection with relay 110, is provided for sensing the forward limit of rotation of shaft 15. Similarly, a limit switch 115, having normally closed contacts A in series connection with relay 111, is provided for sensing the rearward limit of rotation of shaft 15.

When the right limit of router head movement is reached, limit switch 112 is actuated to open contacts 112A and thereby de-energize relay 110 to open contacts 110C. As contacts 110C are opened, electromagnetic clutch coil 93 controlling router head movement to the right is de-energized. As limit switch 112 is operated contacts 112B, in series connection between relay 111 and contacts 28C, are closed so that relay 111 is energized through contacts 28C. As relay 111 is energized, contacts 111C, in series with electromagnetic clutch coil 94, are closed so that clutch coil 94 is energized. As the operator senses this reversal of router head movement, he merely moves wheel 28 to the left to close contacts 28D which are in series connection with relay 111. On the other hand, the operator may maintain wheel 28 in its hard over position to the right for automatic cycling of the router heads back and forth along rails 24. Energization of clutch coil 94 corresponds to operation of the router head drive mechanism for movement of the router heads from right to left. The router heads, accordingly, are moved from right to left under power from motor 92 until the router heads reach their left limit of travel, at which time limit switch 113 is operated to open contacts 113A and close normally open contacts 113B. Contacts 113B are connected in series between relay 110 and contacts 28D. As limit switch 113 is operated, coil 93 and relay 110 are energized while relay 111 and coil 94 are de-energized. Accordingly, the router heads are moved from left to right according to the procedure described above.

If it is desired to maintain power rotation or oscillation of shaft 15, it is only necessary to pull control handle 27 away from housing 11 to close contacts 27A. Once this is done motor 92 is operative if contacts 28B-are closed. In analyzing the operation of the shaft oscillating mechanism, the operation of limit switches 112 and 113 may be ignored. Accordingly, it is assumed that contacts 112A and 113A are closed. To commence power operation of the shaft rotating mechanism, hand wheel 27 or 29 is given a turn, say to the right, to commence movement of the stereotype plate mounted to shaft 15 from the rear of cavity 12 toward the front of the cavity by closure of switch contacts 27C. This motion corresponds to forward movement of shaft 15. This initial movement of either Wheel 27 or wheel 29 to the right energizes relay 110. Energization of relay 110 closes contacts 110C to energize clutch coil 93 for powered forward rotation of shaft 15. Wheel 27 or 29 is maintained in its right position to keep contacts 27C closed. Reversal of shaft rotation is vaccomplished as limit switch 114 operates to open contacts 114A and to close contacts 114B, thereby energizing relay 111 and clutch coil 94. The operator may either follow reversals of shaft rotation with movement of wheel 27 (or wheel 29), or he may keep contacts 27 closed for oscillation of shaft 15 through an arc of 180. In the latter case, the reversals of motion are accomplished by operation of limit contacts 114A, 114B, 115A, 115B, and by relay contacts 110A, 110B, 111A and 111B. The arc of oscillation of the cylinder shaft may be preselected as desired. In a presently preferred embodiment of the invention, the arc is 180 in extent.

The automatic router head traversing mechanism, or the mechanism for producing cyclic oscillation of shaft 15, is useful in the present invention when it is desired to rout out all but a small section of material on a stereotype plate. For example, if all but a narrow vertical area (an area circumferential to shaft 15) of a stereotype plate is to be routed away, the automatic shaft oscillation mechanism is engaged so that all that the opeartor need do is provide manual traversing of one of the spindles laterally of the plate. Similarly, if all but a narrow horizontal area (an area parallel to shaft 15) of a stereotype plate is to be routed away, the automatic traversing mechanism is engaged and angular displacement of the stereotype plate relative to a selected lowered spindle is accomplished manually.

While the invention has been described above in conjunction with specic apparatus, this has been by way of example only for the purposes of illustrating a preferred form of the present invention. The foregoing description should not be understood to restrict the scope of the present invention. Rather, the scope of the present invention is defined in the following claims.

What is claimed is:

1. In a router including means for mounting a curved plate concentric to a horizontal axis, a router head, means for mounting the router head for movement along a path above and parallel to the horizontal axis, and means for moving the router head along the path, the improvement comprising (l) a pair of vertically disposed spindles each adapted for releasably receiving a routing tool at its lower end,

(2) mounting means for mounting each spindle to the router head for rotation about a vertical axis and for reciprocation along the vertical axis between a raised and a lowered position of the spindle,

(3) controllable means for moving a selected one of the spindles to its lowered position and for rotating the selected spindle, and

(4) interlock rneans for (a) controlling the controllable means for rotating the lowered spindle in a direction for cutting operation of the routing tool received therein, and for (b) assuring that the other spindle is raised when the selected spindle is lowered.

2. In a router including means for mounting a curved plate concentric to a horizontal axis, a router head, rneans for mounting the router head for movement along a straight path above and parallel to the horizontal axis, and means for moving the router head along the path, the improvement comprising (l) a pair of vertically disposed spindles each adapted for releasably receiving a clockwise cutting routing tool at its lowered end,

(2) mounting means for mounting each spindle to the router head for rotation about a vertical axis and for reciprocation along the vertical axis between a raised and a lowered position of the spindle,

(3) controllable means for rotating one spindle in a clockwise direction and for rotating the other spindle in a counterclockwise direction,

(4) selectively operable means for moving one of the spindles to the lowered position thereof so that a routing tool engaged with the lowered spindle is engageable with the curved plate, and

(5) interlock means for (a) controlling the controllable means for rotating the lowered spindle in a clockwise direction, and for (b) operating the selectively operable means for raising the other spindle when said one spindle is lowered.

3. A router according to claim 2 wherein the controllable means includes a drive belt and means for driving the belt consisting of a belt drive pulley, reversible means for rotating the pulley, and a belt tensioning pulley, each spindle having a spindle drive pulley connected thereto for rotation of the spindle in response to rotation of the spindle drive pulley, the belt being engaged with only the belt drive pulley, the tensioning pulley and the spindle drive pulleys.

4. A router according to claim 3 wherein the spindle drive pulleys are spaced apart from each other longitudinally and transversely of the path of movement of the router head and the belt drive pulley and the tensioning pulley are spaced apart from each other along the path of movement of the router head, the drive belt passing around the tensioning pulley to around the one of the spindle drive pulleys which is closest to the belt drive pulley along the router head path and then around the other spindle drive pulley to the belt drive pulley, whereby one of the spindle drive pulleys is rotated clockwise in response to movement of the belt and the other spindle drive pulley is rotated counterclockwise.

5. A router according to claim 3 wherein the belt drive pulley, the tensioning pulley and the spindle drive pulleys are disposed substantially in a common horizontal plane.

6. A routing machine comprising a movable router head, means for guiding movement of the router head along a straight path, a pair of rotatable spindles mounted to the router head for rotation relative to the router head about parallel axes, each spindle being adapted to receive a routing tool, a spindle drive pulley connected to each spindle, and means for rotating the spindles including a single drive belt, a belt drive pulley, a single belt tensioning pulley and reversible means for rotating the belt drive pulley, the spindle drive pulleys being spaced apart from each other along and transversely of said path, the belt drive pulley and the tensioning pulley being spaced apart along rand adjacent said path, the belt passing from the belt drive pulley to the tensioning pulley, then around the spindle drive pulley which is closer to the belt drive pulley along the path to around the other spindle drive pulley to the belt drive pulley, the belt engaging only the belt drive and tensioning poise and the spindle drive pulleys, and means for moving the router head along the path.

7. A router comprising (l) means for mounting a pair of semi-cylindrical stereotype plates in aligned relation concentric to a horizontal axis,

(2) selectively operable means for rotating the pair of plates about the horizontal axis,

(3) a pair of router heads,

(4) means for mounting the router heads for movement along `a straight path disposed above and parallel to the horizontal axis,

(5) means rigidly connecting together the router heads for spacing the heads apart a predetermined distance along the path,

corresponding locations of the plates being spaced apart along the horizontal axis a distance equal to the predetermined distance,

(6) means for moving the pair of router heads along the path,

(7) a pair of vertically disposed spindles mounted to each router head,

each spindle being adapted for releasably receiving a clockwise cutting routing tool at its lower end and being Vmounted to its router head for rotation about a vertical axis and for reciprocation along, the vertical axis between a raised and a lowered position thereof,

(8) controllable means for rotating corresponding ones of each pair of spindles in a clockwise direction and for rotating the other of each pair of spindles in a counterclockwise direction,

(9) selectively operable meansy for moving at least one of two corresponding spindles to the lowered position thereof so that a routing tool engaged with the lowered spindle is engageable with the corresponding curved plate, and

(l) interlock means for (.a) controlling the controllable means for rotating the lowered spindle in a clockwise direction, and

(b) operating the selectively operable means for raising the other of the pair of spindles when said at least one spindle is lowered.

8. In a router according to claim 1 stationary shield means disposed around the means for mounting the curved plate .and dening below and along the path of router head movement an elongated opening through which the spindles depend from the routing head, and movable cuttings shield means closing the opening and movably connected to the stationary shield means on opposite sides of the opening, the movable shield means being connected to the router head for movement therewith, the spindles passing through the movable shield means.

9. A router according to claim 8 wherein the movable shield means comprises a strip of material characterized in that it coils upon itself, the strip being disposed along the opening, the strip having a width greater than the transverse extent of the opening, and including means for guiding the strip in response to movement thereof as the router head is moved and for restraining the strip from coiling upon itself for a length of the strip at least as long as the elongate extent Iof the opening.

10. A router for letterpress stereotype plates comprising a horizontal rotatable shaft, means for mounting a semicircularly curved stereotype plate to the shaft concentric with the shaft axis, a router head, means for mounting the router head for movement along a path above and parallel to the shaft, a pair of spindles mounted to the router head for rotation about substantially parallel substantially vertical axes and depending from the router head toward the shaft, each spindle at its lower end being adapted to receive a clockwise cutting routing tool, means for rotating the spind-les, selectively operable means for lowering a selected one of the spindles, means operable in response to operation of the selectively operable means for assuring that the other spindle is in its raised condition relative to the router head and for controlling the means for rotating the spindles so that the selected spindle is rotated clockwise, and controllable means for rotating the shaft and for moving the router =head along the path including a motor and selectively operable means for coupling the shaft or the router head but not both to the motor for movement thereof in response to operation of the motor.

11. A router according to claim 10 including means for defining two spaced limits of router head travel along said path, and means operable in response to operation of the selectively oper-able means of the controllable means when said selectively operable means is disposed to couple the router head to the motor for automatically cycling the router head between the two limits of travel thereof.

12. A router according to claim 10 including means for defining two limits of shaft rotation, and means operable in response to operation of the selectively operable means of the controllable means when said selectively operable means is disposed to couple the shaft to the motor for oscillating the shaft between the two limits of rotation thereof.

13. A router according to claim 10 wherein the spindles are spaced from each other longitudinally and transversely of said path and wherein the spindle rotating means comprises -a drive belt, a belt drive wheel, a belt tensioning wheel and a spindle drive pulley secured to each spindle, the wheels and pulleys being disposed essentially in a common plane for rotation about substantially parallel axes, the belt passing in the plane from the drive wheel to the tensioning Wheel and then parallel to the path to and around the spindle pulley farthest along the path from the tensioning pulley and then to and around the other spindle pulley so that the spindle pulleys rotate in opposite directions and then parallel to the path to the drive wheel.

14. A router according to claim 10 wherein the spindle rotating means comprises a beflt engaged with the spindles so that the spindles rotate in opposite directions in response to movement of the belt, and the means for assuring that the selected spindle is rotated clockwise includes means interconnected between the means for lowering the selected spindle and the spindle rotating means for moving the belt to impart clockwise rotation to the selected spindle.

15. A router for letterpress stereotype plates comprising a horizontal rotatable shaft, means for mounting a semicircularly curved stereotype plate to the shaft concentric with the shaft axis, a router head, means for mounting the router head for movement along a path above and parallel to the shaft, a pair of spindles mounted to the router head for rotation about substantially parallel substantially vertical -axes and depending from the router head toward the shaft, each spindle at its lower end being adapted to receive a clockwise cutting routing tool, means for rotating the spindles, selectively operable means for lowering a selected one of the spindles, means operable in response to operation of the selectively operable means for Iassuring that the other spindle is in its raised condition relative to the router head and for controlling the means for rotating the spindles so that the selected spindle is rotated clockwise, manually operable means for moving the router head along the path, manually operable means for rotating the shaft, a motor, clutch means, and means for operating the clutch to couple the motor to the router head or the shaft but not to both for overriding the manually operable means associated with the one of the head and the shaft coupled to the motor, and means for cycling the one of the head and shaft coupled to the motor between two limits of travel thereof.

16. A router for letterpress stereotype plates comprising a horizontal rotatable shaft, means for mounting a pair of substantially identical semicircularly curved stereotype plates to the shaft concentric with the shaft axis and in axial alignment with each other, a pair of router heads, means for mounting the router heads for movement along a path above and parallel to the shaft, means for fixing the router heads relative to each other so that corresponding points of the heads are spaced from each other along the path a distance equal to the spacing along the shaft of corresponding points of the stereotype plates, a pair of spindles mounted to each router head for rotation about substantially parallel substantially vertical axes and depending from the router head toward the shaft, each spindle at its lower end being adapted to receive a clockwise cutting routing tool, means for rotating all the spindles simultaneously including a drive belt, a drive pulley on each spindle, a belt drive pulley, a single belt tensioning pulley, and a motor coupled to the belt drive pulley for rotating the same, the belt engaging only the belt drive, tensioning and spindle drive pulleys and being disposed thereon so that the spindles on each head rotate in opposite directions and corresponding spindle drive pulleys rotate in the same direction in response to movement of the belt, selectively operable means for lowering at least one spindle of the two pairs corresponding spindles from its head toward the shaft, means operable in response to operation of the selectively operable means for assuring that the other spindles are in their raised condition relative to their router heads and for controlling the spindle drive motor so that the selected spindle is rotated clockwise, and controllable means for rotating the shaft and for moving the router head along the path including a second motor and selectively operable means for coupling the shaft or the router head but not both to the second motor for movement thereof in response to operation of the second motor.

17. A router according to claim 16 including means for defining two spaced limits of router head travel along said path and means operable in response to operation of the means for coupling the second motor to the router heads for automatically cycling the heads between the two limits of travel thereof.

18. A router according to claim 16 including means for defining two limits of shaft rotation and means oper- 16 lable in response to operation of the means coupling the second motor and the shaft for oscillating the shaft between the two limits of rotation thereof.

References Cited by the Examiner UNITED STATES PATENTS 459,655 9/91 Satterlee 90-15 XR 692,487 2/02 Shurmer 90-14 1,466,811 9/23 Thacher '90-15 XR 1,598,202 8/26 .Ducer 90-15 XR 2,322,129 6/43 Hawkins 90-15 XR 2,644,371 7/53 Baker 90-14 2,785,262 3/57 Bourns 308-35 XR 2,983,199 5/61 Daugherty 90-15 WILLIAM W. DYER, JR., Primary Examiner.

LEON PEAR, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTION Patent No 3,209,653 October 5, 1965 Leland H Satre et allc It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 8, line 9, for "Swich" read switch line 60, after "energizes" insert solenoid 96 to close normally open contacts 96B discolumn 9, line 49, for "elevation" read invention Signed and sealed this 31st day of May 1966.

SEAL) Ittest:

RNEST W. SWIDER EDWARD I. BRENNER ttesting Officer Commissioner of Patents 

1. IN A ROUTER INCLUDING MEANS FOR MOUNTING A CURVED PLATE CONCENTRIC TO A HORIZONTAL AXIS, A ROUTER HEAD, MEANS FOR MOUNTING THE ROUTER HEAD FOR MOVEMENT ALONG A PATH ABOVE AND PARALLEL TO THE HORIZONTAL AXIS, AND MEANS FOR MOVING THE ROUTER HEAD ALONG THE PATH, THE IMPROVEMENT COMPRISING (A) A PAIR OF VERTICALLY DISPOSED SPINDLES EACH ADAPTED FOR RELEASABLY RECEIVING A ROUTING TOOL AT ITS LOWER END, (2) MOUNTING MEANS FOR MOUNTING EACH SPINDLE TO THE ROUTER HEAD FOR ROTATION ABOUT A VERTICAL AXIS AND FOR RECIPROCATION ALONG THE VERTICAL AXIS BETWEEN A RAISED AND A LOWERED POSTIION OF THE SPINDLE, (3) CONTROLLABLE MEANS FOR MOVING A SELECTED ONE OF THE SPINDLES TO ITS LOWERED POSITION AND FOR ROTATING THE SELECTED SPINDLE, AND (4) INTERLOCKING MEANS FOR (A) CONTROLLING THE CONTROLLABLE MEANS FOR ROTATING THE LOWERED SPINDLE IN A DIRECTION FOR CUTTING OPERATION OF THE ROUTING TOOL RECEIVED THEREIN, AND FOR (B) ASSURING THAT THE OTHER SPINDLE IS RAISED WHEN THE SELECTED SPINDLE IS LOWERED. 